Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Aug. 19, 2021	Dec. 31, 2020	Jul. 31, 2000
Debt Instrument [Line Items]
Unamortized debt issuance cost		$ 43		$ 28
RS Cogen
Debt Instrument [Line Items]
Noncontrolling interest, ownership percentage		50.00%
Senior Notes \| 8.73% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)		8.73%
Senior Notes \| Term Loan Due 2026
Debt Instrument [Line Items]
Stated interest rate (percent)		0.20%
Maximum borrowing capacity		$ 23
Debt instrument term	5 years
Senior Notes \| Term Loan Due 2026 \| Taiwan Chlorine Industries, Ltd.
Debt Instrument [Line Items]
Noncontrolling interest, ownership percentage		60.00%
Senior Notes \| 0.875% Senior Notes Due 2024
Debt Instrument [Line Items]
Stated interest rate (percent)		0.875%	0.875%
Aggregate principal amount			$ 300
Senior Notes \| 2.875% Senior Notes Due 2041
Debt Instrument [Line Items]
Stated interest rate (percent)		2.875%	2.875%
Aggregate principal amount			$ 350
Senior Notes \| 3.75% Senior Notes Due 2061
Debt Instrument [Line Items]
Stated interest rate (percent)		3.375%	3.375%
Aggregate principal amount			$ 450
Line of Credit \| 8.73% Senior Notes Due 2022 \| RS Cogen
Debt Instrument [Line Items]
Stated interest rate (percent)		8.73%
Noncontrolling interest, ownership percentage		50.00%
Maximum borrowing capacity					$ 75